Primary Motor Cortex

The primary motor cortex (M1, or somatomotor area) occupies a large portion of the precentral gyrus (Brodmann area 4) and typically executes movements that are selected and planned by other areas of the brain.

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Each hemisphere has a primary motor cortex and both are organized by body region or somatotopically.

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The medial and superior portions control the actions of the feet, legs, trunk, and hands.

The lateral portions control the actions of the head, mouth, and throat.

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The primary motor cortex on one side of the brain controls the muscles on the opposite side of the body.